What is the difference between a virus and a worm in cybersecurity?

• A. A virus requires user action to spread, while a worm does not
• B. A virus is a type of software, while a worm is hardware
• C. A virus is always more harmful than a worm
• D. A virus operates only online, while a worm works offline

Answer: (A)

The distinction between a virus and a worm lies primarily in how they propagate and infect systems. A virus requires user action to spread, meaning it typically attaches itself to a host file or program, and it will only execute and replicate itself when the user opens or runs that file. This characteristic makes user interaction a key factor in the virus's ability to spread.

On the other hand, a worm is self-replicating and can spread across networks independently, without needing user intervention. It exploits vulnerabilities in network protocols or software to duplicate itself and propagate across connected systems, making it capable of spreading rapidly and widely without relying on human action.

The other responses involve incorrect or misleading concepts. For instance, a worm is not hardware; both viruses and worms are forms of malicious software or malware. Additionally, it is not accurate to categorize viruses as always more harmful than worms since their impacts can vary greatly depending on their specific coding and intent. Lastly, both viruses and worms can operate both online and offline, depending on their design and the context of their implementation. Thus, the accurate portrayal of their operational mechanisms highlights the key difference in their methods of propagation.